Carburetor



9 z j E s,

T. M. BALL CARBURETOR Filed May 13. 1949 Dec. 1, 1953 @-4- f4 JNVENTOR.'azwds /afz BY Patented Dec. l, 1953 lll-Iil-Il'l'.ElDy STATES).

Mawr oFFicE;

CARBURETOR corporation of Delaware Application May 13,' 1949, Serial No.93,135

(Cl. 2in-41)' 9..Claims. 1.-'.

This'inventionv` relates toA an improved internal combustion` enginecarburetor vand more particu-` larly to an improved step up or power jetthere-- 1n:

It isl now conventional practice to supply fluid froml the reservoirof#a` carburetor tothe fuel mixture passage thereof through arelativelysmall metering orifice which predetermines` the economymixture of the carburetor. When en.- richment offthe mixture is-requiredfor power a1-soca1led'stepup valve-is opened: inorder to allow-fvanvadditional supply` of fuelto iiowI from; the' reservoir of Vthecarburetorv to the fuel mixtureV passage. Iny the lpresentinventionopening ofi-thisv step-up. `valvefis` produced byy aVA mechanism whichis responsive. to changesiin .manifold vacuum and' which. provides*aplurality. of stepups.` With thismultiple-step-updevice.a change froman economy.` mixtureto aV fullspower mixture is.I made-by. gradual;increments. foundtobe. particularly desirable for use on enginesequipped; with .a supercharger.

The; term manifoldfvacuum as used herein is intended to refer to thepartial vacuum which is present` inl varying degrees inA theV manifold.downstream; of the throttle valve under engine operating. conditions;andl which is determined bythe. relationship.` of engine` speed tothrottleposition. The?. term* drop lin manifold. vacuuml referstoanincrease in absolutev pressure -inthe manifold;

In the drawings:

Fig. 1 is;asectionalelevational view, ofa. down draft` carburetorhavingmy. multiple step-uprdevice incorporated therein;

Fig. 2 is a. fragmentary view of the multiple step-up, device of Fig., 1showing thef partsY in their respective positions after one step-up.;has occurred;

Fig. 3 is.k a fragmentary View similar. to Fig. 2s but showing the partsintheir respective positionsv afterA a. secondr increment ofvstep-up-.has oc-l curred;

Fig. 4 is a fragmentary view of a modied'stepup device;

Fig. 5- is a partial View of the. device-,of Fig. 4.. showing therelative position of thef parts under high. vacuum. conditions;

Fig. Gis a View similar to Fig. 5-but showing the position of thepartsunder mediumvacuum conditions; and

Fig. 7 is a view similar to Fig. 5 but showing the position of the partsunder low Vacuum condition..

Referring to. thedrawings, the carburetor comprises an assembly of abody I0, an air horn ll,

rIhis has f been I adapted to be connected by a fuel line (not-- shown)to a source of supply of fuel such as-afuel pump (not shown). Theairhorn I I isprovided Iwith atubular part I5 which serves asan airinletto a fuel mixturepassage- I 6. The egress of the fuel mixtureto-theengineintake.mani fold is controlled by athrottlevalve- I'I.

The body portion I0"of-thecarburetor isprovided with a fuel reservoirIB-and the intake-.of

fuel thereto-from the nipple .I 4 `is controlledl by` aneedlevalve ISwhich is operated by a conventional float mechanism 201whichpredetermines.

the fuel level in the-reservoir.

The main fuel injection means controls.l the mixture with air of fuelpassing through a. metering jet 2l. withm-ixture chamberv I6 through anorifice; 23:

Tubular passage 24.which is connectedvia .ductsA 25 and 26 to atmosphereis concentrically disf..

posed within passage 222 and provided with a plurality. of holes21 inits sidewalls. AirA entering tubular passage24. escapes throughholesl2'I and mixeswith fuelin passage 22* and the atom..

izedI mixtureis discharged from 4orifice .$23.

Liquid for enginefidling is. drawn byY manifold vacuum from passage. 22through idling tube; 34;.

which is connected through a passage 3l toa passage 38; The latterpassage. has an orifice:

39- open to theatmosphere and an orifice 40 operatively connected`r toan idling-j et 4 I A mechanism 28 which includes the multiple step-updevice referred to herein is adapted'- to` vary the fuel mixture ratioin response to theY degree of' manifold vacuum. This mechanisml includesa spring loaded piston 29 adaptedV to reciprocate in response tovariations in manifold vacuum transmittedthrough anorice 30 andapassagel 3l. A rst valve 35 controls the now of,`

liquid fuel through an orifice 3B which connects the f uelj reservoir I8and thepassage 22. A second; Valve 4 5 controls the flow of liquid fuelthrough an orice 46 which connects the fuel reservoir- IB and thepassage 22. Piston 28, is forced upward by a spring 41 whichphas aspringv rate, such that manifold vacuum in 'passage 3|. can overcome. itto retract piston 129. downwardly. Piston 29 carries an arm 48, which issecured thereto and adaptedu to reciprocate therewith. Valve stems 35.and` 45. each penetrate an open; ing in. arm 48 and each are providedwith anup. set head 49 and 50 respectively. A spring 5I. sur-` roundsvali/e stem. 3.5i and... reacts against arm; 48;

Tubularv passage22 connects. jet 2 I4.

accinge and a washer 52 carried on valve stem 35. A similar spring 53surrounds valve member 45 and reacts against arm 48 and a washer 54carried by valve stem 45. A guide member 55 is received within anopening in arm 48 and serves to guide the latter as it slides up anddown in response to movement of piston 29. v l

1t should be noted that in Fig. 1 the valve stem 85 is shown asconstructed of a shorter length than the valve stem 45 so that when bothvalves are closed as shown in Fig. 1 the offset head of stem is incontact with arm 48 while the offset head 56 of arm 45 projects abovethe arm 48. It is apparent that when the manifold vacuum decreases inpassage 3l sufficiently for the spring 41 to raise piston 29 and arm 48upwardly that arm 48 will first lift valve stem 35 and thus open orifice36 so that an additional amount of fuel will be delivered from the fuelreservoir I8 to passage 22 and the parts will assume the position shownin Fig. 2 with the orice 36 open and the orifice 46 closed. Furtherdecrease in manifold vacuum permits spring 41 to further elevate piston29 and arm 48. The further elevation of arm 48 lifts valve stem 35further but this has no effect upon the operation of the carburetor forthe valve stem 35 was already clear of orifice 35. However, the furtherupward movement of arm 48 causes upset head 58 to engage arm 48 wherebyvalve stem is lifted clear of orifice 46 thereby providing a stillfurther passage for fuel from the fuel reservoir I8 to passage 22. Thereis thus provided a normal supply of fuel to the engine and twoadditional step-ups which may be brought into action upon decrease inmanifold vacuum.

It should be noted that the washers 52 and 54 engage abutments on thevalve stems 35 and 45 respectively and that the springs 5I and 53 urgethe valve stems downwardly toward their valve closing positions.

Although a pair of valve stems 35 and 45 have been illustrated ascontrolled by arm 48, it should be understood that a larger number ofvalve stems could be employed to provide additional increments of powermixture of fuel and air if desired.

In Fig. 4 a modified form of the invention is illustrated. The functionaccomplished by this form of the invention is similar to that alreadydescribed in reference to Figs. 1, 2 and 3 although s the mechanicalarrangement of parts is somewhat altered and a single orifice two stagevalve is substituted for the pair of valves used in the Fig. 1 form ofthe invention. The arm 48 carried by the manifold vacuum responsivepiston 29 is provided with an opening at 6U which a valve stem 62penetrates. The carburetor body l0 is provided with a valve housingarrangement 64 having an axial passage therethrough. The axial passagein valve housing 64 has a restricted portion 66 and a valve seat 68formed therein. The valve stem 62 is provided with av needle likeextension 18 and an enlarged portion 12 having a tapered portion 14adapted to cooperate with the valve seat 68. The needle like extension19 is adapted to penetrate the restricted orifice 66. Thus when theportion 14 of the valve stem rests upon the seat 68 there is no flow offuel through restricted portion 66. When the valve stem 62 rises enoughso the portion 14 uncovers valve seat 68 fuel flows through therestricted orifice 66, but the quantity thereof is limited for theeffective size of the orifice is reduced by the presence of the needlelike extension 18. Further elevation of the valve stem 62 lifts theneedle like' extension 16 out of the restricted orifice 66 s that itseffective area is utilized and a larger flow of fuel to the carburetoris provided. There are thus provided valve positions which accommodateeither no fiow of fuel through the orifice 66, a first reduced quantityof fuel or a maximum quantity of fuel. 1n order to accomplish this andprovide the three operative positions for valve stem 62 in response tomovement of arm 48 and piston 29 certain springs are provided on valvestem 62. A pair of lock nuts 16 are threaded on to the upper end of stem62 above arm 48'. A washer 18 circumscribes stem 62 and a pin 88 limitsdownward movement thereof. A spring 82 is retained between arm 46 andwasher 18. A second pair of lock nuts 84 are threaded to the centralportion of stem 62. A second spring 85 surrounds stem 62 and reactsagainst the lock nuts 84 and a washer 88 which loosely surrounds thelower portion of stem 62 and on occasion abuts against the upper surfaceof valve housing element 64. The enlarged portion 12 of valve stem 62 isprovided with a shoulder 89 below washer 88. The spring 82 is relativelystrong while the lower spring 86 is relatively weak.

Referring to Fig. 5, it will be seen that under high vacuum conditionsthe valve is completely closed with the tapered portion 'I4 of the valvestem in engagement with the valve seat 68 and springs 41, 82 and 86cooperate to oppose the vacuum which maintains piston 29 in its downwardposition. On a rst reduction in manifold vacuum the combined effect ofthe springs 41, 82 and 86 tends to elevate piston 29 and the partsassume the intermediate position illustrated in Fig. 6 in which spring86 is compressed while spring 82 is extended and relaxed with the arm48' in contact with lock nuts 16. Under these conditions the taperedportion 14 of the valve stem 62 is lifted above the valve seat 68although the needle like extension 18 still penetrates the restrictedorifice 66. On further reduction in manifold vacuum the combined effectsof spring 41 and spring 86 further elevate the piston 29. ment of piston29 elevates arm 48', which through lock nuts 18, elevates valve stem 62until washer 88 is lifted off valve housing element 64 and the spring 86is allowed to extend until washer 86 engages shoulder 89. like extension19 is lifted entirely out of the restricted orifice 66 to provide amaximum fiow of fuel through the orifice 66. The spring 82 serves anadditional useful purposein that it permits piston 29 and arm 48 toovertravel relative to valve stem 62. the necessity of having piston 29reach the bottom of its stroke simultaneously with the seating of thetapered portion 14 of valve stem 62 on valve seat 68.- Thus, even thoughthe valve seat 68 is engaged the vacuum may move piston 29 downward anadditional increment.

I I claim:

l. In a carburetor adapted to supply fuel to an vinternal combustionengine having vacuum producing means, means defining a fuel reservoir,means defining a fuel and air mixing chamber, means defining an openfluid passage connecting the reservoir and the mixing chamber, meansdefining first and second supplemental fiuid passages connecting saidreservoir and said chamber, a valve in each of said supplementalpassages and a common operator for said valves operable to open one ofsaid valves under a first vacuum condition in said vacuum producing Thisupward move- At this time the needle This is desirable for it obviates"7^` :.f' .u mennen@ Qperable, .Q 09?... underasecohd vacuum condi on insaid vacuum producing meansu, i ;'.I.;:;:f,'. y

s2.: .In a. earburetenada .ted te nnniyiuel i en internal combilstie.engine-lining meeuw-PIO; dueine means. nie .defining meansdenins.affnelzanelair.- ...s means denmngan Open-.Quid neeSaseenneCiIisthelreservoir and the ,mXinefeheinleertmeenS ,def nainsnrst;andseeondsnnplemenial :fluid 10a-S.-VV sages .connecting .saidreservoir .andrsaidfehe ber-,1.a valve ,in each of;V.Said-.S.u..1e.p1.e.n1entail De sages;Y amovable element assoeiatedwith.. Sa el valves@ and.-,operab1e te ,sequentially enen; Seid,valvesfwhen Innyedin. a first. dir eti 11,; a spring... urging saidelement Ato, movein said .first vdirection and-means denninaa passageexposing l said ele; ment -tey vacuum: from seid; yeeuumf ,producingmeans to oppese-.eadrenrine whereby underfa flrstzvacuum condition fsaidl spring moves said element .sufficiently te enen @neef',Saidsyalieerelldf under a second vacuum condition said 'springs movessaid element sufficiently to open both of said valvesz. y.1

3. In a carburetor adapted to supply fuel to an internal ,combustionengine having vacuumi producing means, means defining a fuel reservoir,means defining a fueland-air mixing chamber, meansfdefining an openfluid passage connecting the reservoinand the mixing chamber, means`defilling firstand second supplemental fluidl passages connecting saidreservoir and said chamber, a-valvei-n eachvof said supplementallpassages and a vacuum responsive device operably connected to one ofsaidvalves to open said one valve when aA predetermined vacuum conditionexists in said vacuum "producing means, said device having a lostmotion,I connection with .the other valveso that said last mentionedvalve is opened when a second predetermined f-vacuu-m. condition isobtained insaid vacuum producing means.

4. In, a carburetor adaptedto supply `filetto an internal combustionengine having vacuum producing means, means defining a fuel reservoir,means defining a fuel and air mixing chamber, means dening an open fluidpassage connecting the reservoir and the mixing chamber, means deningrst and second supplemental huid passages connecting said reservoir andsaid chamber, a valve seat associated with each of said supplementalpassages, a valve stem associated with each of said seats, a vacuumresponsive device having a piston element adapted to move in a rstdirection in response to a decrease in vacuum in said vacuum producingmeans and to move in a second direction in response to an increase insaid vacuum, means carried by said piston element and adapted to moveone of said valve stems off of its associated seat in response to apredetermined movement of said piston element in said rst direction andto move the other of said valve stems oil of its associated seat inresponse to continued movement of said piston element in said firstdirection.

5. In a carburetor adapted to supply fuel to an internal combustionengine having vacuum producing means, means defining a fuel reservoir,means defining a fuel and air mixing chamber, means defining an openfluid passage connecting the reservoir and the mixing chamber, meansdening a supplemental fuel passage connecting said reservoir and saidchamber, a valve adapted to control the ow of fuel through saidsupplemental passage, said valve including a movable stem having a rstopen position adapted to acn Yci adaptedwto accommodate. a reduced4flovv# o'f'ful meanstoftherebyiducemoyement offsald c pgsitioniwhich.prevents". the. iloiv' of' any/fuelr through said ,supplemental A ment,A'passafge'ffrnirig mea'msv Ytiex'pose said con;A trol element tovacurnin said valcuunilprodiici i en @enseignent .dejenme n' respete, toi'ineneaeed nieuwe eenditenefin 'Se-id ,Veeue-efe ducing means, al firstspring means opposing all" mo of ,saidV element saidy firstdirection'gaid' liningV ai supplemental fuel passage .connecting saidreservoir and saidf chamber, af single,l o'rf'it'ie'r two.Y stageKAvalve` controlling', the .flovvl 0f l.fuel through said.. supplemental'passage, said Vvalve having a .valve stemv mountedfor linear. move,-ment, a vacuum .responsive .device mouteclii linear movement iny.response vto variations inl vacuum in said va'ciuin'lproducingv means,an4 arm tioned adjacent stem, a flrstspringintrposedV Abetweensaid`| armand said stem'` and' adau `tedjso oppose. movement ,offsai'd larm in,one direction relativetol said stem', said" stem having an abutmentengageable by said arm to accommodate movement of said stem with saidarm when said arm moves in a second direction, a second spring havingone end abutting a portion of said stem and the other end positioned toengage said fixed abutment whereby under a first vacuum conditionmovement of said arm in said first direction by said device is opposedby both of said springs and movement of said stem with said arm in saidsecond direction is facilitated by cooperation of said arm with theabutment on said stern and the movement in this second direction isassisted by said second spring.

7. A carburetor adapted to supply fuel to an internal combustion enginehaving a manifold and means for producing a vacuum in said manifold,said carburetor including a body part defning a fuel reservoir, an airand fuel mixing chamber and a main fuel passage connecting saidreservoir and said mixing chamber, said body part being provided withauxiliary fuel passage means operably interposed between said fuelreservoir and said mixing chamber and adapted to provide an additionalsupply of fuel for said mixing chamber, valve means movable to a closedposition, an open position and a restricted flow position relative tosaid auxiliary uid flow passage means, a piston slidably mounted in saidbody part for movement in response to variations in manifold vacuum, anarm carried by said piston and first and second springs positioned tosequentially oppose movement of said arm and provide a lost motionconnection between said arm and said valve means to accommodate abruptmovement of said valve means to said positions in response to movementof said piston.

8. A carburetor adapted to supply fuel to an internal combustion enginehaving a manifold and means for producing a vacuum in said manifold,said carburetor including a body part defining a fuel reservoir, an airand fuel mixing chamber and a main fuel passage connecting saidreservoir and said mixing chamber, said body part being provided withauxiliary fuel passage means operably interposed between said fuelreservoir and said mixing chamber and adapted to provide an additionalsupply of fuel for said mixing chamber, valve means movable to a closedposition, an open position and a restricted flow position relative tosaid auxiliary fluid flow passage means, a spring opposed pressuredifferential operated element mounted for movement in response tovariations in manifold vacuum, a member carried by said element andhaving a lost motion connection with said valve means and first andsecond springs acting upon said valve means and operable to move saidvalve means rapidly from said closed position to its restricted flowposition and to its open position at predetermined conditions ofmanifold vacuum.

k9. A carburetor adapted to supply fuel to an internal combustion enginehaving a manifold and means for producing a vacuum in said manifold,said carburetor including a body part defining a fuel reservoir, an airand fuel mixing chamber and a main fuel passage connecting saidreservoir and said mixing chamber, said body part being provided withauxiliary fuel passage means operably interposed between said fuelreservoir and said mixing chamber and adapted to provide an additionalsupply of fuel for said mixing chamber, valve means movable to a closedposition, an open position and a restricted ow position relative to saidauxiliary fluid flow passage means, a pressure differential operatedelement mounted for movement in response to variations in man1- foldvacuum, a first spring operable to move said element in response todecrease in manifold vacuum, a member carried by said element and havinga lost motion connection with said valve means so that a first incrementof movement of said element by said first spring occurs when manifoldvacuum decreases Without opening said valve means, a second springacting upon said member and said valve means and cooperating with saidfirst spring during the aforementioned first increment of movement, saidsecond spring being operable only during relative movement between saidmember and said valve means, a third spring acting upon said valve meansand reacting upon said body part during a portion of the movement ofsaid valve means from its closed position to its open position and meanscarried by said valve means and operable to carry said third spring outof operative relation with said body part when said valve means hasmoved a predetermined amount in a direction tending to open said valve.

THOMAS M. BALL.

References Cited in the ille of this patent UNITED STATES PATENTS

